Abundance, Diversity, and Depth Distribution of Planctomycetes in Acidic Northern Wetlands

Members of the bacterial phylum Planctomycetes inhabit various aquatic and terrestrial environments. In this study, fluorescence in situ hybridization (FISH) was applied to assess the abundance and depth distribution of these bacteria in nine different acidic wetlands of Northern Russia. Planctomycetes were most abundant in the oxic part of the wetland profiles. The respective cell numbers were in the range 1.1–6.7 × 107 cells g−1 of wet peat, comprising 2–14% of total bacterial cells, and displaying linear correlation to the peat water pH. Most peatland sites showed a sharp decline of planctomycete abundance with depth, while in two particular sites this decline was followed by a second population maximum in an anoxic part of the bog profile. Oxic peat layers were dominated by representatives of the Isosphaera–Singulisphaera group, while anoxic peat was inhabited mostly by Zavarzinella- and Pirellula-like planctomycetes. Phylogenetically related bacteria of the candidate division OP3 were detected in both oxic and anoxic peat layers with cell densities of 0.6–4.6 × 106 cells g−1 of wet peat

Influence of anionic surfactant on stability of nanoparticles in aqueous solutions

Dispersion and aggregation of nanoparticles in aqueous solutions are important factors for safe and effective application of nanoparticles, for instance, in the oil industry. As conventional oil reserves are depleted, it is necessary to advance chemical enhanced oil recovery (cEOR) techniques to develop unconventional oil reservoirs. Nanoparticles modified by surfactants can be a promising reagent in cEOR. These nanomaterials can reduce interfacial tension and change the wettability of reservoir rock, which leads to an increase in oil recovery. However, the application of nanoparticles is limited by their substantial aggregation in aqueous solutions. The purpose of this work is to select nanoparticles for obtaining stable sols in water in the presence of an anionic surfactant and to optimize the conditions (pH) for further modifying the nanoparticles with the anionic surfactant. Sodium dodecyl sulfate (SDS) is used as an anionic surfactant. The aggregation of oxide and carbon nanoparticles in water and anionic surfactant solutions was studied by laser diffraction, dynamic and electrophoretic light scattering methods. Most of the studied nanoparticles in water form aggregates with bi-, three- and polymodal particle size distributions. TiO2 nanoparticles obtained by plasma dynamic synthesis form the most stable sols in anionic surfactant solutions. The range of 5–7 pH is defined as optimal for their modification with surfactants. The stability of carbon nanoparticles in aqueous solutions increases significantly in the presence of a surfactant. The obtained results form the basis for further research on the modification of marked nanoparticles in surfactant solutions

Exploring the diversity of cancer-associated fibroblasts: insights into mechanisms of drug resistance

Introduction: Among the various stromal cell types within the tumor microenvironment, cancer-associated fibroblasts (CAFs) emerge as the predominant constituent, exhibiting a diverse array of oncogenic functions not intrinsic to normal fibroblasts. Their involvement spans across all stages of tumorigenesis, encompassing initiation, progression, and metastasis. Current understanding posits the coexistence of distinct subpopulations of CAFs within the tumor microenvironment across a spectrum of solid tumors, showcasing both pro- and antitumor activities. Recent advancements in single-cell transcriptomics have revolutionized our ability to meticulously dissect the heterogeneity inherent to CAF populations. Furthermore, accumulating evidence underscores the pivotal role of CAFs in conferring therapeutic resistance to tumors against various drug modalities. Consequently, efforts are underway to develop pharmacological agents specifically targeting CAFs.Methods: This review embarks on a comprehensive analysis, consolidating data from 36 independent single-cell RNA sequencing investigations spanning 17 distinct human malignant tumor types.Results: Our exploration centers on elucidating CAF population markers, discerning their prognostic relevance, delineating their functional contributions, and elucidating the underlying mechanisms orchestrating chemoresistance.Discussion: Finally, we deliberate on the therapeutic potential of harnessing CAFs as promising targets for intervention strategies in clinical oncology

Comparison of ACINUS, caspase-3, and TUNEL as apoptotic markers in determination of tumor growth rates of clinically localized prostate cancer using image analysis

The balance between apoptotic and proliferative processes determines the enlargement of a tumor. Accurate measurement of apoptotic and proliferative rates from diagnostic prostate biopsies would allow calculation of tumor growth rates in a population-based prostate cancer (CaP) study. Automated image analysis may be used if proliferation and apoptotic biomarkers provide clearly resolved immunostained images

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

The ‘‘Detectability Window’’ Method to Take into Account Observational Selection in the Statistics of Exoplanets Discovered through Radial Velocity Measurements

International audienceA method of correcting the statistical data of the exoplanets discovered through radial velocity measurements is proposed. The statistical regularities of the mass and orbital period distributions of exoplanets have been analyzed

Atomic Force Microscopy Study of the Temperature and Storage Duration Dependencies of Horseradish Peroxidase Oligomeric State

This paper presents an investigation of the temperature dependence of the oligomeric state of the horseradish peroxidase (HRP) enzyme on the temperature of its solution, and on the solution storage time, at the single-molecule level. Atomic force microscopy has been employed to determine how the temperature and the storage time of the HRP solution influence its aggregation upon direct adsorption of the enzyme from the solution onto bare mica substrates. In parallel, spectrophotometric measurements have been performed in order to estimate whether the HRP enzymatic activity changes over time upon the storage of the enzyme solution. The temperature dependence of the HRP oligomeric state has been studied within a broad (15–40 °C) temperature range. It has been demonstrated that the storage of the HRP solution for 14 days does not have any considerable effect on the oligomeric state of the enzyme, neither does it affect its activity. At longer storage times, AFM has allowed us to reveal a tendency of HRP to oligomerization during the storage of its buffered solution, while the enzymatic activity remains virtually unchanged even after a 1-month-long storage. By AFM, it has been revealed that after the incubation of a mica substrate in the HRP solution at various temperatures, the content of the mica-adsorbed oligomers increases insignificantly owing to a high-temperature stability of the enzyme

The Mass Distribution of Transit Exoplanets from the Mass–Radius Relationships: the Structurization within Planetary Systems

International audienceMost transit exoplanets (85%) were discovered with the Kepler space telescope. However, the mass, which was measured mainly with the radial velocity method, is known only for ~15% of them. The mass of an exoplanet may be estimated by its radius from the statistical dependences based on the observational data, though no unambiguous interrelation between the mass and the radius of planets exists. Here, we calculate the earlier unknown masses of exoplanets from four statistical mass–radius relationships (Bashi et al., 2017; Chen and Kipping, 2017; Ning et al., 2018, and the averaged dependence derived) and added the results to the distribution of planets with known masses. The mass distributions of transit exoplanets obtained in this way are analyzed with taking into account the observational selection effect inherent in the transit method. The distributions are approximated by the power law ∂N/∂M ~ Mα, where the exponent (α < 0) is determined by the maximum likelihood estimation for the samplings acquired with four mass–radius relationships: α = –2.12 ± 0.03, –2.09 ± 0.03, –1.94 ± 0.03, and –2.27 ± 0.04. Moreover, for one of these distributions, we determine the parameters of the power law, the exponent of which differs on three intervals (with the boundaries at 0.025, 0.28, and 1.34 Jupiter masses): –1.99, –0.62, and –2.88. We also conclude that there is no evidence of the interrelation between the mass of an exoplanet and its average distance to the host star (the structurization within planetary systems), if this distance is smaller than 1 AU; besides, the dependence of the exponent α on the considered mass interval is analyzed. The above estimates appertain to exoplanets detected by the space telescopes: Kepler Space Telescope and Transiting Exoplanet Survey Satellite (TESS) (these exoplanets compose group 1). The masses of the other transit exoplanets, which were detected by ground-based instruments, were known (they compose group 2). For the latter group, the exponent α is estimated at –2.21 ± 0.04. In general, the results of our analysis agree with those of the earlier statistical and theoretic studies. A key idea of the present paper is to apply the model interrelations between the mass and the radius of exoplanets to the analysis of the mass distribution of exoplanets on the basis of the recent data of observations

The Dependence of the Mass Distribution of Exoplanets on the Spectral Class of Host Stars

International audienceWe analyze the mass distributions of exoplanets of three groups: transit planets discovered by the Kepler telescope, those found in ground-based observational programs and with the CoRoT satellite, and planets discovered in the vicinity of red dwarfs (M class) with the radial-velocity method. The dependence of the mass distributions of the Kepler transit planets on the spectral class of the host stars (F, G, and K classes) are considered. Taking into account the most significant factors of observational selection, which are different for each of the groups of planets, it has been shown that the mass distributions of exoplanets can be described by a universal power law with the index close to −2: dN/dm ∝ m−2. For the planets orbiting the stars of different spectral classes (F, G, K, and M), no statistically significant difference has been found